Bearing cavities of gas turbine engines are normally pressurized with air and sealed to prevent leakage of lubricating oil from the bearing cavities. Determining acceptable air leakages through the seals is one of the design parameters of the bearing cavities. The integrity of a seal is confirmed when air leakage therethrough is below the acceptable design parameter of air leakage. Integrity tests can be required during or after engine assembly in order to evaluate the bearing seals.
Known methods for testing seals are normally used for cases of relatively small air leakages through the seals or for relatively large volumes of tested cavities. However, the bearing cavities of gas turbine engines may have relatively small volumes while permitting relatively large acceptable air leakages through the seals. Therefore, an improved method of testing seals in a sealed bearing cavity is desirable.